The secrets of tape measures. Do you know everything about the essential construction tool?

A tape measure is an essential tool on any construction site. Without it, it is impossible to make accurate measurements. However, do you choose your tape measure consciously? Do you know all its possibilities? Do you know why some tape measures are more expensive while some are cheaper? We answer these and other questions in the following text, revealing all the secrets of this small but meaningful tool.

How is a tape measure built?

The fundamental element of a tape measure is, obviously, a tape. It should be properly profiled so that it does not break when pulled out to a distance of only a few centimeters. It is located in the housing (cassette). Since the measure is to roll up, you need a suitable mechanism along with a brake. A popular solution is the so-called "classic brake" - if you do not tighten the lock, the measure will roll. However, a reverse brake is present in many products, such as PR-60-05 i PR-60-11. It is a construction in which the tape locks automatically when ejected. To roll up the tape it is necessary to release the brake lock. The cassette itself is constructed in various ways, which significantly affects its durability and ergonomics of use.

Often the cassettes are designed to further facilitate the taking of measurements. For example, the PRO tape measure and the PRO Milestone tape measure have markings that allow you to measure the length from the back of the housing. There is a hook at the end of the tape that is fastened with rivets. And, as it will turn out in a moment, this inconspicuous hook is one of the most important elements that hides many secrets!

Overhang length and tape profile

Let anyone who did not play with his father's measure in childhood, checking how long it can be extended before it breaks, be the first to throw a stone. PRO tape measures are so well profiled that this type of "fun" takes on a blush. The absolute record holder in this field is the X-Rocker, which has a reach of up to 4 m! The situation is similar in the case of PRO Milestone, which offers an overhang of up to 50% of the tape length! It is useful when working with elements located far away from us, and especially when these elements are situated high.

Imagine how much easier it is to easily extend the tape a few meters up, for example, to check the height from the floor to the ceiling joists. Note that in good quality tape measures the following applies: the longer the tape, the wider the tape top.

Most of the 3 m length tape measures have a 16 mm wide tape, and the longer ones, e.g. 8 m, usually 25 mm. This also significantly affects the overhang length. Standard tape measures have one graduation. Sometimes, however, for the convenience of use, double-sided printing is used and the result can be read regardless of the side of the tape. Such a procedure was used in the PR-60-11 model.

Quality of measures - approvals and accuracy classes

Length	Class
Length	I [mm]	II [mm]	III [mm]
1 m	±0,2	±0,5	±1,0
2 m	±0,3	±0,7	±1,4
3 m	±0,4	±0,9	±1,8
5 m	±0,6	±1,3	±2,6
8 m	±0,9	±1,9	±3,8
10 m	±1,1	±2,3	±4,6
20 m	±2,1	±4,3	±8,6
30 m	±3,1	±6,3	±12,6
50 m	±5,1	±10,3	±20,6
100 m	±10,1	±20,3	±40,6

Before choosing a tape measure, think about the accuracy class you need for your work! Remember that each measure, even a certified measure, has a certain tolerance. For example, a Class III measure at a distance of 5 m has a tolerance of ± 2.6 mm.

For comparison, a class I measure at the same distance will have a tolerance of only 0.6 mm, so the possible error is much smaller.

All PRO measures meet the strict EC tolerance requirements for classes I and II. In our offer you won't find class III measures. You will see what this means in the table below. Remember that the PRO offer includes both short professional measures, 2 m long (PR-45-12), as well as very long ones (PR-60-02).

The secrets of tapes

If you are wondering what are the differences between a tape measure for a few bucks and the one for a dozen or so, the answer may be the quality of the tape itself. First of all, the material is important. PRO uses ultra-tough, high-quality carbon steel to ensure the tape is of the same thickness along its entire length. This has an impact on the tool life, after all, differences in thickness on individual sections of the tape adversely affect the retraction mechanism.

In the case of lower quality tape measures, a problem that appears quite quickly is rust, which blocks the retraction and makes it difficult to read the measurement. PRO solved this problem by subjecting the edges of the measures to process resulting in round edges which minimize the risk of corrosion. To be even more sure that rust is not a threat to PRO tools, the measures are placed for more than 2 hours in a 5% NaCl solution! And they don't rust! In addition, PRO covers the measuring tops with a layer of nylon. It protects against scratches which most often lead to rusting. In addition, this layer reduces light reflection - you'll see the scale better when working on a sunny day.

Metrówka PRO X-Rocker

A good quality tape measure is resistant to hits, strikes, and bumps

When it comes to bumps, it's not just the tool dropping. Professional PRO rolls are protected by the use of high-quality thermopolymer material and thermoplastic rubber that guarantees adequate shock absorption in the event of a fall. Sometimes, as in the case of the PR-60-06 model, the housing is metal and covered with a protective chrome coating.

Miara zwijana PRO-60-06

Also in this matter, tests are carried out, which consist in checking the behavior of the material after a fall from a height of 1.2 m. It turned out that the fall did not affect the functionality of the tape measures and the shape of the housing.

The tape hook strikes the housing while retracting. That is why some products, e.g. the PR-60-05 measure, are equipped by PRO with a shock-absorbing bumper. As we mentioned, impact resistance is not all about endurance.

PRO prides itself on the fact that before tools are offered to customers, they undergo rigorous durability tests. The springs are fatigue tested and the tapes are pulled 3,000 times 1.8 cm outside the measuring range. Even so, the spring is not damaged!

Tape measure hook - a key element affecting the convenience of measurement

When choosing a retractable measure, first of all, pay attention to whether the hook moves. If so, good! All the hooks in the PRO brand measures are movable, thanks to which the measurement is more accurate. After all, the hook itself is also thick, and the lack of movement would make the measurement inaccurate by even a few millimeters. The hook itself should be made of stainless steel, and this is the case with PRO products. The number of rivets with which the hook is attached to the measuring table is important. The absolute minimum is two rivets that ensure the stability of the hook. The professional X-Rocker measure, which uses as many as four rivets, is a revelation in this respect! However, it is assumed that at least three rivets are used for high-end measures, for example in the aforementioned Milestone measure.

It is a solution that strengthens the connection of the hook with the tape and guarantees a longer life of the entire tool. It is often the case that shorter measures (3 meters long) have two rivets and longer measures have three rivets. Because the hook is often subjected to great forces - after all, it is the starting point for the measurement from which the measure unrolls - manufacturers sometimes additionally strengthen this element. An example is a solution present in measure PR-60-06. The hook is 20% thickened. In the hooks, you can also find various additional functions that make work easier. Strong magnets are often mounted. These are useful when working with metal parts, especially vertical ones. In addition, you can find special holes for nails and screws, which allow easy hooking and guarantee that the hook will stick to them, and the measure will not start to curl. As you can see, the hitch in a tape measure is inconspicuous, but it is a key element.

Which tape measure is the best?

If you are wondering which tape measure to choose, there are a few things to consider. First of all, it is impact strength - despite everything, tool falls do occur on the construction site. Secondly, resistance to corrosion, especially after contact with water. Finally, you need to pay attention to the reach offered by the measure and the quality of the hook. In the PRO offer, you will surely find a product that meets your expectations. If you are looking for the highest quality, durability, and accuracy, we suggest starting with the PRO Milestone models, which won the Design Award 2016 for its unique design, and the PRO X-Rocker, which is marked as ultra-strong and shock-resistant for a reason.